Apparatus for heating air.



e. WESTINGHOUSE & A. M; GOW. APPARATUS FOR HEATING AIR: APPLICATION FILED 8EPT.17,-1903.

?,967 Patented Nov; 29, 1910.

f gymj-vitozi '12) all whom it may concern:

UNITED STATES PAT NT OFFICE.

GEORGE WESTINGHOUSE, OE PITTSBURG, AND ALEXANDER M. GOW, OE EDGEWOOD PARK, PENNSYLVANIA; SAID GOW ASSIGNOR TO SAID WESTINGHOUSE.

APPARATUS FOR HEATING AIR.

g Specification of Letters Patent.

Patented Nov. 29, 1910.

Original application filed May 2, 1903, Serial No. 155,258. This application filed September 17, 1903. Serial Be it known that we, GEORGE WESTING- HOUSE and ALEXANDER M. Gow, citizens of the United States, and residents, respectively, of Pittsburg'and Edgewood Park, in

the county of Allegheny and State of Pennsylvania, have jointly lnvented certain new and useful Improvements in Apparatus for Heating Air,-of whichthe following is a specification.

The object of our invention is to obtain heated air by the addition to the volume of air to be heated of the hot products produced in a combustion chamber, by the combustion of gas therein. The invention is especially designed to obtain hot blast for use in a smelting furnace. We are aware that it has been heretofore proposed to burn oil and add the heated products of combusion to the air to be heated. We do not propose the use of oil, but any carbonaceous materlal which can be worked to advantage in a gas producer. Such material we propose to convert into producer gas and we also propose to consume this gas as fast as produced in a combustion chamber over the fuel bed, the resultinghot products of combustion mixing with the volume of air to be heated and raising its temperature to the desired degree. We also provide means whereby the amount of gas made and the consequent temperature of blast attained shall be at all times under control and shall, if desired, be automatically controlled.

In the drawings accompanying this appllcation and forming a part thereof, the figure. illustrates in partial vertical section an apparatus designed tocarry out our invention.

Referring now to the drawings, 1 is: a smelting furnace of any well-known type, for convenience we have shown a familiar type of water-jacketed furnace. air supply pipe to this furnace, connected by branch pipes, 3, 3, to the twyers, 4, 4, by means of which air is admitted to the furnace hearth, 5. The pipe 2 is connected to a gas producer, 6, by means of pipes, 7 and 8, and a water-cooled valve, 9, is provided ,by which the connection between pipes 7 and 8' maybe closed. The gas producer 6 is of suflicient size topermit of a large com- 2 is the evolved in the producer. Pipes 11 and 12, connect the gas producer 6 to the tubular preheater, 13, and a valve, 14, is provided whereby pipe 11 may be 'cut off from pipe 12. The tubular preheater 13 is connected by pipe 15 to a blower or fan, 16, which supplies the air for conducting the smelting operation. A smaller blower, 17 receives air by a shunt line, 18, from the main air line, 15, "and discharges this air through pipes, 19 and 20, into the bottom of the fuel bed in gas producer 6. Steam is admitted from any convenient source through pipe 21, the amount being regulated by a valve, 22. The top extension 40, of the furnace is provided with a damper, 30, for permitting or preventing the exit of the waste gases therethrough. When this damper is closed, the waste gases from the furnace 1 pass through a pipe, 23, and around the tubes, 24, 24, 24, of the tubular preheater. The air to the furnace passes through these tubes and re ceives a preliminary heating from the waste gases of the furnace. An exhaust fan, 25, assists the discharge of the waste gases from the preheater 13 through the stack, 26. Below the preheater 13 is provided a chamber 27 for the catching of dust blown over from the smelting furnace. Doors, 28, 28, are provided for the removal of this dust. Between pipes 20 and 19 there is located an automatically actuated valve, 29; the operation of which is controlled by a thermostat 32, located in the pipe 7. An electrically operated valve device 33 is arranged to operate the valve 29 and is included in an electric circuit 34, in -which the thermostat 32 is also included. The valve 29 is of the butterfly type and is operatively connected with an electro-magnetic device 4041 of any well-known type and arranged so as to.

gpen and close the valve more or less, as is esired. r I

A thermostatic device 32 of any wellknown type, located in the pipe 7, controls the flow of current through the circuit 34 and consequently through the coils of the electro-magnetic device and the thermostat is arranged to break the circuit when the heat of the blast passing through the pipe 7 falls below a certain predetermined temperature. The electro-magnetic device is preferably so constructed that when the circuit is broken the valve 29 is opened. As the temperature of the blast increases the thermostat, which is arranged to control the amount of'current passing through the circuit 34, allows the electro-magnetic device to be energized'in different degrees corre sponding to the degrees of temperature encountered and this causes the valve 29 to be opened more or less. By this arrangement the amount of air discharged by the blower 17 is automatically controlled and the valve 29 is automatically opened when the temperature of the blast. falls below a' predetermined point, and is closed to a greater or less extent as the temperature rises. The

- gas producer is provided with the usual reheater and are discharged through stack 26 by means of fan 25. This circulation being established, fan 17 is started, valve 29 is opened, steam admitted by Valve 22, and the production of producer gas begins in gas producer 6. It leaves the fuel bed hot enough to ignite in combustion chamber 10 and its heat of combustion is added to the volume of air passing, raising this volume of air to a temperature dependent upon the volume of gas made. This operation .continues until the body of fuel in producer 6 has been reduced to such an'extent that the producer requires to be recharged. Fans 16 and 17 are then stopped, valves 9 and 14: closed, cover 31 on top of the roducer is removed and a new charge of uel put in theproducer, when it is started up as before. The necessity for shutting the blast off from the furnace may be avoided by the use of two producers in parallel, the. arrangement of valves being such as will permit of one producer being cut out while the other is in operation. The temperature of the blast is dependent upon the amount of air passing through valve 29, inasmuch as this valve controlsthe amount of gas produced. It is understood that the use of steam is merely to prevent the clinkering of the producer and insure its proper working. The use of the tubular preheater 13 is not essential to this method of heating blast, but it is desirable in case the waste gases leaving the furnace are of sufii cient temperature to warrant their use in giving the blast a preliminary heating, to this extent efiecting an economy of fuel in the producer.

In another application Serial Number 155,258, filed May 2, 1903,.claims are made upon the method described herein.

We claim asour invention:

1. The combination with a smelting furnace of a preheater, by the waste gases from the producer located between the pre-heater and the furnace, a combustion chamber in which said pro-heated air has added to it hot prod-, nets of combustion derived from the combustion of gas made, and means dependent on the heat of the blast to said furnace for controlling the operation of said reducer.

2. The combination of a sme ting furnace, a gas producer, ablower discharging air through a combustion chamber connected to the producer and thence to the furnace, and an auxiliary blower discharging air into the bottom of a gas producer, causing the production of gas and its discharge into the combustion chamber, and meansdependent on the temperature of air supplied to said furnace, a gas furnace for controlling the operation of said producer.

Signedat New York, in the county of New York, and State of New York, this 3rd day of September, 1903.

. GEO. WESTINGHOUSE.

Witnesses:

WM. H. CAPEL, H. C. TENER.

Signed at East Pittsburg, in the count y of Allegheny, State of Pennsylvania, this 5th day of September, 1903. I

ALEXANDER M. GOW.

Witnesses:

WESLEY G. CARR, BIRNEY Hmns.

in which air is heated 

